Such cutting tool assemblies have long been known particularly where the cutting insert is replaceably retained in or on a tool holder by screw clamping. With most of such known assemblies handling difficulties are often encountered when removing or replacing the cutting insert, seeing that this usually involves loosening, removal and screw insertion of the clamping screw, whilst at the same time holding the cutting insert.
In our co-pending WO 98/50187, there is provided a cutting tool comprising a cutting insert and a tool holder in which the cutting insert is releasably retained. The cutting insert has a peripheral cutting portion and a central coupling portion constituted by a through bore formed in the body of the cutting insert, the through bore having a plurality of spaced apart, peripherally located, radially directed support wings. The tool holder has a coupling member mounted therein so as to be axially displaceable with respect thereto, the coupling member having a corresponding plurality of radially extending abutment wings for interacting with the support wings of the cutting insert. The cutting tool is assembled by the insertion of the coupling member of the tool holder into the cavity of the cutting insert with the abutment wings passing respectively between successive support wings, rotating the cutting insert relative to the tool holder until the abutment wings overlay the support wings and axially displacing the coupling member of the tool holder in the inward direction thereof until the abutment wings clampingly abut the support wings.
It is an object of the present invention to provide a new cutting tool assembly of the kind disclosed in the co-pending patent application.